Related papers: Uncertainties in Coupling Constant Unification
We explore the possibility of unification of gauge couplings near the Planck scale in models of extended technicolor. We observe that models of the form G X SU(3)_c X SU(2)_L X U(1)_Y cannot be realized, due to the presence of massless…
Supersymmetry (SUSY) remains one of the leading candidates for physics beyond the Standard Model, and the search for SUSY will be a central focus of future collider experiments. Complementary information on the viability and character of…
Using the latest determinations of several theoretical and experimental parameters, we update the Unitarity Triangle analysis in the Standard Model. The basic experimental constraints come from the measurements of |V_ub/V_cb|, Delta M_d,…
We show that it is possible to find an extension of the matter content of the standard model with a unification of gauge and Yukawa couplings reproducing their known values. The perturbative renormalizability of the model with a single…
We revisit the question of gauge coupling unification at the string scale in orbifold compactifications of the heterotic string for the supersymmetric Standard Model. In the presence of discrete Wilson lines threshold corrections with…
We summarize methods and expected accuracies in determining the basic low-energy SUSY parameters from experiments at future e$^+$e$^-$ linear colliders in the TeV energy range, combined with results from LHC. In a second step we demonstrate…
The biggest question in beyond the standard model physics is what are the scales of new physics. Ideas about scales, as well as experimental evidence and constraints, are surveyed for a variety of possible forms of new physics:…
The successes and shortcomings of the Standard Model are reviewed, with emphasis on the reasons motivating the need to extend it. The basic elements of grand unification and supersymmetry are described, exploring their phenomenological…
The string landscape suggests that the supersymmetry breaking scale can be high, and then the simplest low energy effective theory is the Standard Model (SM). We show that gauge coupling unification can be achieved at about 10^{16-17} GeV…
The observational evidence for the recent acceleration of the universe demonstrates that canonical theories of cosmology and particle physics are incomplete---if not incorrect---and that new physics is out there, waiting to be discovered. A…
Recently we proposed a natural scenario of grand unified theories with anomalous U(1)_A gauge symmetry, in which doublet-triplet splitting is realized in SO(10) unification using Dimopoulos-Wilczek mechanism and realistic quark and lepton…
The particle spectrum of the supersymmetric extension of the standard model with a gauge singlet is studied. Soft supersymmetry breaking terms are explicitly chosen to be non-universal according to orbifold string theory. they depend on…
The recent discovery of a 126 GeV boson at the LHC will be followed by a detailed examination of its couplings in order to determine whether this particle is the Higgs boson of the standard model or one of many particles of an extended…
We consider a particular class of threshold corrections to Yukawa couplings and mass relations in the MSSM and supersymmetric grand unified models. We give a complete treatment of Yukawa coupling thresholds at the unification scale $\Mx$…
The possibility of a heavy supersymmetric spectrum at the Minimal Supersymmetric Standard Model is considered and the decoupling from the low energy electroweak scale is analyzed in detail. The formal proof of decoupling of supersymmetric…
Despite the successes of the Standard Model of particle physics, it is known to suffer from a number of deficiencies. Several of these can be addressed within non-supersymmetric theories of grand unification based on $\mathrm{SO}(10)$.…
We derive and experimentally investigate a strong uncertainty relation valid for any $n$ unitary operators, which implies the standard uncertainty relation as a special case, and which can be written in terms of geometric phases. It is…
We investigate whether inclusion of dimension six terms in the Standard Model lagrangean may cause the unification of the coupling constants at a scale comprised between 10^14 and 10^17 GeV. Particular choice of the dimension 6 couplings is…
The present status of Unified Theories is summarized with special emphasis on their possible experimental tests. Outline: i) Unification of couplings; ii) Where can a positive signal come from? iii) HERA anomaly and Unification; iv) Recent…
The supersymmetric standard model with supergravity-inspired soft breaking terms predicts a rich pectrum of sparticles to be discovered at the SSC, LHC and NLC. Because there are more supersymmetric particles than unknown parameters, one…